Spring Boot+Mybatis动态数据源配置

数据源配置：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
<!-- ===============只读数据源的配置=============== -->
<bean id="dataSourceRead" class="com.alibaba.druid.pool.DruidDataSource"
init-method="init" destroy-method="close" p:driverClassName="com.mysql.jdbc.Driver"
p:name="bosscenter" p:url="${jdbc.read.url}" p:username="${jdbc.read.username}"
p:password="${jdbc.read.password}" p:maxActive="10" p:maxIdle="5"
p:minIdle="5" p:initialSize="5" p:testOnBorrow="true" p:poolPreparedStatements="false"
p:validationQuery="SELECT 1" p:filters="stat,config,wall" p:connectProperties="druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000"
p:connectionProperties="config.decrypt=true" />

<!-- ===============可写数据源的配置=============== -->
<bean id="dataSourceWrite" class="com.alibaba.druid.pool.DruidDataSource"
init-method="init" destroy-method="close" p:driverClassName="com.mysql.jdbc.Driver"
p:name="bosscenter" p:url="${jdbc.write.url}" p:username="${jdbc.write.username}"
p:password="${jdbc.write.password}" p:maxActive="10" p:maxIdle="5"
p:minIdle="5" p:initialSize="5" p:testOnBorrow="true" p:poolPreparedStatements="false"
p:validationQuery="SELECT 1" p:filters="stat,config,wall" p:connectProperties="druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000"
p:connectionProperties="config.decrypt=false" />

<bean id="dynamicDataSource" class="com.aa.boss.policy.rpc.dbservice.dao.DynamicDataSource" primary="true">
<property name="targetDataSources">
<map key-type="java.lang.String">
<!--通过不同的key决定用哪个dataSource-->
<entry value-ref="dataSourceRead" key="dataSourceRead"></entry>
<entry value-ref="dataSourceWrite" key="dataSourceWrite"></entry>
</map>
</property>
<!--设置默认的dataSource-->
<property name="defaultTargetDataSource" ref="dataSourceRead">
</property>
</bean>

<!-- define the SqlSessionFactory -->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dynamicDataSource" />
<property name="mapperLocations" value="classpath:policyholdersmybatis/*.xml">
</property>
<property name="typeAliasesPackage" value="com.aa.boss.policy.rpc.api.pojo" />
<property name="configLocation" value="classpath:mybatis.xml" />
</bean>

<!-- scan for mappers and let them be autowired -->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"
id="mapperScannerConfigurer">
<property name="basePackage" value="com.aa.boss.policy.rpc.dbservice.dao" />
<property name="sqlSessionFactoryBeanName" value="sqlSessionFactory" />
</bean>

</beans>
在application.proopertis中配置多数据源连接信息

jdbc.read.driverClassName=com.mysql.jdbc.Driver
jdbc.read.url=jdbc:mysql://111111/11?useUnicode=true&characterEncoding=utf8
jdbc.read.username=111
jdbc.read.password=

jdbc.write.driverClassName=com.mysql.jdbc.Driver
jdbc.write.url=jdbc:mysql://111111/11?useUnicode=true&characterEncoding=utf8
jdbc.write.username=111
jdbc.write.password=11定义一个DBContextHolder, 用于保存当前线程使用的数据源名：

import org.springframework.util.StringUtils;

/**
* Created by lfd on 2017/7/7.
*/
public class DBContextHolder {
public static final String DATA_SOURCE_READ = "dataSourceRead";
public static final String DATA_SOURCE_WRITE = "dataSourceWrite";
//用ThreadLocal来设置当前线程使用哪个dataSource
private static final ThreadLocal<String> contextHolder = new ThreadLocal<String>();
public static void setDBType(String DBType) {
contextHolder.set(DBType);
}
public static String getDBType() {
String dataSource = contextHolder.get();
if (StringUtils.isEmpty(dataSource)) {
return DATA_SOURCE_READ;
}else {
return dataSource;
}
}
public static void clearDBType() {
contextHolder.remove();
}
}

自定义一个javax.sql.DataSource接口的实现，只需要继承Spring实现好的父类AbstractRoutingDataSource即可
import org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource;

/**
* Created by liufangda on 2017/7/7.
*/
public class DynamicDataSource extends AbstractRoutingDataSource {
@Override
protected Object determineCurrentLookupKey() {
return DBContextHolder.getDBType();
}
}
最后在你需要用到的接口的Controller层加入这么一句代码
DBContextHolder.setDBType(DBContextHolder.DATA_SOURCE_WRITE);这时你这个接口用的就是dataSourceWrite数据源，由于我在上面的配置中配置了默认的dataSource，所以你不加这句代码默认是会用dataSourceRead数据源的